Abstract: Applicator for coloring or bleaching product for hair tresses or other hair treatment, includes a lower jaw, planar and smooth on its base, constituting a coloring compartment or area fed by the treatment product, and an upper jaw, jointed with the lower jaw, maintained closed upon it through the action of a rebound spring, requiring the tip of the jaw which comprises a joint with a soft lip to clamp the selected tresses previously added to the coloring area on the lower jaw. The joint having a lip (9) has a tapered shape along its width making a distribution and spreading area for applying color, where the traction of the tool towards the rear naturally crushes a corner of dye and causes its natural diffusion inside each tress of hair. One or more moveable reservoirs containing the coloring composition, clamped above the upper jaw, feed the coloring compartment by pressing a button.